covering

遮盖或隐藏之物；覆盖物；铺在或包在另一物上的东西。

That which covers or conceals; a cover; something spread or laid over or wrapped about another.

覆盖或包裹的天然物体

a natural object that covers or envelops

动词“覆盖”所指的动作。

Action of the verb to cover.

覆盖某物的人造物(通常用于保护、遮蔽或隐藏)

an artifact that covers something else (usually to protect or shelter or conceal it)

一组集合U_i,其并集包含U；也指每个U_i均为开集的集合；或每个U_i均包含于U的集合。

A collection of sets U_i such that their union contains U; such a collection with the additional property that every U_i is open; such a collection with the additional property that every U_i is contained in U.

通过遮挡视线来隐藏某物存在的行为

the act of concealing the existence of something by obstructing the view of it

建立两个拓扑空间之间关系的特殊映射,使得一个空间在局部上像是另一个空间的若干副本。形式上,是连续映射π:E→X,对X中每一点x,存在离散空间D_x和开邻域U,使得π−1(U)=⊔_{d∈D_x}V_d,且π|_{V_d}:V_d→U是同胚。

A special kind of map that establishes a relationship between two topological spaces in the sense that, under the action of the map, the one looks locally like several copies of the second: Formally, a continuous map π:E→X between topological spaces such that there exists, for every point x in X, a discrete space D_x and an open neighborhood U of x such that π−1(U)= displaystyle ⨆_(d∈D_x)V_d and π|_(V_d):V_d→U is a homeomorphism for every d∈D_x. See Covering space on Wikipedia.Wikipedia